1. Field of the Invention
The present invention relates to an apparatus for measuring a trajectory and a flight distance of a ball and more particularly to a ball measuring apparatus which is suitable for measuring a trajectory and a flight distance of a golf ball.
2. Description of the Related Art
As an apparatus for measuring a trajectory of a golf ball, conventionally, an apparatus using a CCD camera has been proposed. Japanese Laid-Open Patent Publication No. 2001-145718 has disclosed an apparatus for measuring a trajectory of a ball using at least one CCD camera for detecting a maximum point and at least one CCD camera for detecting a drop point. Japanese Laid-Open Patent Publication No. 2003-42716 has disclosed an apparatus for measuring a trajectory of a ball which comprises at least two CCD cameras provided behind a hitting position and ahead of a target position and a calculating portion for calculating coordinates of a position of the ball by the triangulation technique.
Moreover, Japanese Patent No. 2953672 has disclosed a golf apparatus for measuring an initial velocity of a golf ball by using a radar and presuming a carry from the initial velocity of the ball which is measured. The measuring apparatus using the radar is utilized as means for detecting a distance to an object, a velocity of the object and the like. For a type of the radar, a laser radar, a millimeter-wave radar or the like is used. Since the millimeter wave radar is influenced by a bad weather such as rain or fog, it is utilized in some fields. Japanese Laid-Open Patent Publication No. 2004-227111 has disclosed a security system for detecting an invader by using the millimeter wave radar. Japanese Laid-Open Patent Publication No. 2002-207077 has disclosed a running support apparatus for a car which comprises radar means for detecting a distance from an object positioned ahead of the car by using the millimeter wave radar. Japanese Laid-Open Patent Publication No. 11-72558 has disclosed a landing inducing apparatus to be used when accurately inducing a flight vehicle to a landing space by using the millimeter wave radar.
The apparatus for measuring a trajectory by means of a camera is easily influenced by a weather such as rain or fog and a brightness. The millimeter wave radar can carry out a measurement which is rarely influenced by the weather. Furthermore, the millimeter wave radar can carry out the measurement at night without an illumination. However, it has been found that the trajectory and flight distance of the ball cannot be measured with high precision by simply using the millimeter wave radar.